As a start, the following affect the "attrition rate": * Assembly machine program * Machine calibration and maintenance * Part characteristic * Machine setup * Proximity of part to end of tape * Machine vision calibration * PCB layout * Pad factors * Using a leader with components

As an aside: since no "big name" company other than General Electric that talks the "six sigma game" is profitable, what�s the fascination? Sounds like another management fad rolling down the pike, eh?

Wowzer, there's tons of hits on the net for "six sigma BB". Six sigma stuff gives about one tenth the hits of "Total Quality Management". Hummm.

They give these five day training courses on histograms, parento charts, and whatnot to get a BB. Cool. For those that can only stand the pain for two days, they give a GB. [Mikey is that the other Butts sister?]

I had no idea that this was so um, er involved. Mr. M. Harry should be very pleased.

I am surprise that you get 99.5% pick-up rate out from the HS-50, unless you are refering to 0201 chip size. I can easily get 99.8% for 0603 and 99.6% for 0402 out from a Panasonic MV2F, and these machines have no adaptive pick-up. To get 99.8% from HS-50 for 0603 or 0402 should be piece of cake.

You can easily get 99.8% for 0603 and 99.6% for 0402 out from a Panasonic MV2F, and these machines have no adaptive pick-up. To get 99.8% from HS-50 for 0603 or 0402 should be piece of cake. Anyway, is getting 99.8% pick-up = 6 sigma process?

Dave, I did assume Angela meant components ready for pick up. It would be too time consuming for any machine to measure the component availability prior to pick up. If we assume that the feeder advances in a rate of six sigma ( 3 defects per mio ) there must be another cause why the component cant be picked, if the defect rate is for example 3 sigma. Siemens and others detect missing components by the vacuum level and optically. If the machine uses both electrical signals of feeder advance and the feed back signal feeder ready, but there is no component on the nozzle, we can ( in a six sigma probability ) assume that there was an empty pocket. Stefan

Hi Dave, I think 6 sigma is here to stay. Unlike any other programs like ISO, six sigma goes to the people�s mind. With drastic examples like � you would not fly a plane which reaches its destination in a three sigma probability � you start to think about quality issues. I can not make any judgements about the efficiency of these programs. Apparently, as a German you grow up with a different understanding of quality, precision and accuracy. Six sigma signs and banners are not required in Germany or Switzerland. Is Angela on the right path ? I don�t know. The pick up availability itself does not improve the placement quality and the few components rejected may not be worth the time to think about it.

However, if we go deeper into this subject we will find that the tolerances in the tape dimension, together with the tolerances in the component dimension, make component feeding technical more challenging than getting the component onto the board. Eventually, the lack of tolerances can lead to a real defect. If the component is as high as wide, it may be presented and placed on the edge. Is this a defect ? Some say yes because the print is not readable.

I encourage everyone to look beyond the start and stop key of a machine, if it is for a black belt or out of own interest.

The vacuum measurement on the HS 50 is the same than on all other 12 nozzle heads of the Siplace or SP 120. There are three separate vacuum circuits. One for pick up at six o�clock, one in reject position at 5 o�clock and another circuit for the other ten nozzles. The component can be programmed with or without vacuum leakage, like for LED�s or Melf�s. The management information data give you some clue about the defect rate per feeder / component and nozzle.

I will provide more information on my web site. Thank you for your comments. Stefan

Stefan: Thanks for the clarification on the Siemens machine operation.

Yes Stefan, Germany and some other countries have wonderful apprentice programs. Generally, we Americans have the patience of a staving gerbil for such things.

Is the ON button the green or the red one?

It�s possible that the ISO-9000 foolishness will codify the six sigma tools, as you say, but experience and cynicism says otherwise �

* As I flip through my workbooks from a Du Pont "Solving Tough Quality Problems" course [circa 1987], it�s just like "Ground Hog Day". [By the by, speaking of "Ground Hog Day", did Bill Murray go through eight cycles of before he won the girl [A McDowell]? (A bar bet.)] We are being taught about the importance of the customer; flow charts; parento diagrams; posing problem causes; testing theories with scatter plots, experiment design, histograms, and sequence plots; solve or prevent problems; look at results; hold gains; needs of the team; and management role. Ooops, I copied that from the Du Dont course index.

* Steve Luftig�s "Introduction To SPC And Capability" course [written in 1985, revised in 1987] lays-out descriptive statistics, control chart theory, process control and capability for variable data, and process control and capability for attribute data. Again, we seem to be paving the same ground, but this time it has a skin coat of beige. [Oooops not beige, it�s black, hmm.]

* Blush of attraction wears off quickly. As I stated earlier, except General Electric, none of the big name six sigma proponents make money. When it comes to making your quarter, it doesn�t take a rocket scientist to cut training and such. SHOW ME THE MONEY!!!!

Now, I know that I won�t get a true adherent�s tail in a knot by stating that ISO-9000 is foolish. I�m just stating facts. Consider that in 1979 British Standards Institute xeroxed a copy of the then ancient 1960s vintage MIL-Q-9858A to produce BS 5750. [In truth, by 1979 the Brits had fumbled around with the limp wristed Mo 5 and BS 5170 for more than two decades before being struck with a lightning bolt of wisdom to create 5750.] In a wrong headed attempt to erect a barrier to US products, in 1987 the nascent European Community bulled ISO-9000, itself a xerox copy of BS 5750, through the International Organization For Standardization. What a joke!!! We learned how "comply" long before those dithering bureaucrats in Tha Hague [or where ever they are] could spell it!!!

After 13 years of trying to produce results [other than making registrars rich] with this seriously flawed document, what do they do? Trash the whole ISO-9000 thing and xerox the Baldridge Award criteria [circa, get this, 1987] and call it "ISO-9000-2000". Choice or what? [And registrars love changing the baseline, because it give them new ways to keep getting rich.]

Ho-hum. Let me put continuing with this rant aside for another day [I know you�re all sick of this, but the sound of rodents� feet scurrying in the over-head that you hear is people preparing to give you an opportunity to rewrite your quality manual to be complaint.]. One development in recent years that pleases me is the improved ease of use, dissemination, and application of experimental design techniques [e.g., Bhote, Taguchi].

Finally Ang, [without knowing how you selected "availability" as your project focus ( and recognizing that probably you are too far down the road to make course corrections, which makes these comments less than meaningful )]. I would like to see you select at theme like "improve [blank (placement?)] accuracy of [blank (SOIC in tubes?)] by [blank (97 scadzillion percent?)]" or reduce mis-printed boards by [blank]. Problems I have with availability are: * Linkage between availability and the paragon "making a very nice board" seems tenuous * You are whining about how tough it�s going to be to meet the change goal. [I think you should have a difficult, but immanently achievable goal on your first project. (Yano, low hanging fruit) Impossible goals should come on succeeding projects.] * Since you can�t measure it, as Stefan has said, proof of success will prove difficult.